Detection of Siglec‑1/CD169 in Human PBMCs by Flow Cytometry.
Human peripheral blood mononuclear cells (PBMCs) either (A) untreated or (B) treated with 20 ng/mL Recombinant Human IFN‑ gamma (Catalog # 285-IF) for 24 hours were stained with Mouse Anti-Human Siglec‑1/CD169 Monoclonal Antibody (Catalog # MAB5197) followed by Allophycocyanin-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # F0101B) and Mouse Anti-Human CD14 PE‑conjugated Monoclonal Antibody (Catalog # FAB3832P). Quadrant markers were set based on control antibody staining (Catalog # MAB002).
Preparation and Storage
Reconstitute at 0.5 mg/mL in sterile PBS.
Reconstitution Buffer Available
The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below. *Small pack size (SP) is shipped with polar packs. Upon receipt, store it immediately at -20 to -70 °C
Stability & Storage
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
6 months, -20 to -70 °C under sterile conditions after reconstitution.
Siglecs are sialic acid specific I-type lectins that belong to the immunoglobulin superfamily. Structurally, they are transmembrane proteins with an N-terminal Ig-like V‑set domain followed by varying numbers of Ig-like C2-set domains (1, 2). Human Siglec-1, also known as sialoadhesin and CD169, is a 175-185 kDa glycoprotein. It contains a 1622 amino acid (aa) extracellular domain (ECD) with one Ig-like V‑set domain and 16 Ig-like C2-set domains, a 21 aa transmembrane segment, and a 44 aa cytoplasmic domain (3). Within the ECD, human Siglec-1 shares approximately 70% aa sequence identity with mouse and rat Siglec-1. Alternate splicing generates a potentially soluble form of the ECD, and a second isoform with a substituted cytoplasmic domain. Siglec-1 expression is restricted to lymph node and splenic macrophages, plus some tissue macrophages (3). The adhesive function of Siglec-1 is supported by the N-terminal Ig-like domain which shows a selectivity for alpha 2,3‑linked sialic acid residues (3‑5). Siglec-1 binds a number of sialylated molecules including the mannose receptor, MGL1, MUC1, PSGL-1, and different glycoforms of CD43 (6‑9). Its binding capacity can be masked by endogenous sialylated molecules (10, 11). The sialylated and sulfated N-linked carbohydrates that modify Siglec-1 itself are required for ligand binding (6, 7). Siglec-1 is expressed on dendritic cells following rhinovirus exposure, and these DC promote T cell anergy (12). It is also induced on circulating monocytes during systemic sclerosis and HIV-1 infection (13‑15). Siglec-1 can trap HIV-1 particles for trans infection of permissive cells (14).
Varki, A. and T. Angata (2006) Glycobiology 16:1R.
Crocker, P.R. et al. (2007) Nat. Rev. Immunol. 7:255.
Hartnell, A. et al. (2001) Blood 97:288.
Nath, D. et al. (1995) J. Biol. Chem. 270:26184.
Crocker, P.R. et al. (1991) EMBO J. 10:1661.
Martinez-Pomares, L. et al. (1999) J. Biol. Chem. 274:35211.
Kumamoto, Y. et al. (2004) J. Biol. Chem. 279:49274.
Nath, D. et al. (1999) Immunology 98:213.
van den Berg, T.K. et al. (2001) J. Immunol. 166:3637.
Nakamura, K. et al. (2002) Glycobiology 12:209.
Barnes, Y.C. et al. (1999) Blood 93:1245.
Kirchberger, S. et al. (2005) J. Immunol. 175:1145.
York, M.R. et al. (2007) Arthritis Rheum. 56:1010.
Rempel, H. et al. (2008) PloS ONE 3:e1967.
van der Kuyl, A.C. et al. (2007) Plos ONE 2:e257.
Sialic Acid Binding Ig-like Lectin 1
Entrez Gene IDs:
6614 (Human); 20612 (Mouse); 311426 (Rat)
C19orf75; CD169; Siglec1; Siglec-1; SIGLECL1 SIGLEC family like 1
Submit a review and receive a $25US/€18/£15/$25CAN amazon gift card if you include an image - $10US/€7/£6/$10CAN Amazon card for reviews without an image. Limited to verified customers in USA, Canada and Europe.